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a(n) is the smallest number which can be represented as the sum of 3 distinct nonzero fourth powers in exactly n ways, or -1 if no such number exists.
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%I #26 Jul 23 2024 14:57:22

%S 98,6578,811538,5978882,1289202642,292965218,779888018,5745705602,

%T 105760443698,49511121842,1872511131218,281539574498,17673688436978

%N a(n) is the smallest number which can be represented as the sum of 3 distinct nonzero fourth powers in exactly n ways, or -1 if no such number exists.

%C a(16) = 7865870969138. - _Michael S. Branicky_, Jul 23 2024

%e a(2) = 6578 = 1^4 + 2^4 + 9^4 = 3^4 + 7^4 + 8^4.

%e a(3) = 811538 = 4^4 + 23^4 + 27^4 = 7^4 + 21^4 + 28^4 = 12^4 + 17^4 + 29^4.

%Y Cf. A025415, A025419, A230562, A374696.

%K nonn,more

%O 1,1

%A _Ilya Gutkovskiy_, Jul 17 2024

%E a(9)-a(12) from _Michael S. Branicky_, Jul 22 2024

%E a(13) from _Michael S. Branicky_, Jul 23 2024